So H4350 is allegedly 2209 relabelled. In quickload however there is a significant difference. For example in my rifle to get max estimated pressure quickload says you need around 1.5g more 2209 than H4350 for a 6.5x47l. Does anyone know why the difference and what are you guys using?

They are exactly the same powders and either bottles will even share batch numbers (ie, the powder in the bottle if from the same batch).The difference in Quickload will be the normal differences in burn rates between batches. It is likely that with one bottle they had a very fast batch but with the other bottle, they had a very slow batch.